南台灣某區域醫院輸尿管鏡引起Enterobacter cloacae泌尿道感染群突發的調查

An Outbreak of Enterobacter Cloacae Urinary Tract Infections Due to Contaminated Ureteroscopy Instruments in a Regional Hospital in Southern Taiwan

在南台灣某區域醫院，從2010年10月到12月，自18位接受輸尿管鏡檢查的病人的尿液分離出ertapenem-resistant Enterobacter cloacae，因此展開是否發生E. cloacae泌尿道感染群突發的調查。施行輸尿管鏡檢查使用的醫療器材及物品都進行採樣做細菌培養，其中在輸尿管鏡分離出3株ertapenem- resistant E. cloacae，因此修改輸尿管鏡的消毒步驟，包括加強消潔、將0.55% ortho-phthalaldehyde的浸泡時間從10分鐘延長到15分鐘及每週做一次ethylene oxide滅菌。此調查共有21株ertapenem-resistant E. cloacae（其中18株來自病人及3株來自輸尿管鏡），這些細菌都有相同的抗生素敏感試驗，包括對大部分的抗生素呈現抗藥性，只有對amikacin、imipenem及meropenem呈現敏感性。經過感染管制措施的介入，在輸尿管鏡不再分離出E. cloacae，而且也不再有接受輸尿管鏡檢查的病人發生ertapenem-resistant E. cloacae泌尿道感染的病例出現。雖然缺少分子生物學的細菌比對，但是根據這21株細菌都具有相同的抗生素敏感試驗及群突發的調查及處理結果，我們高度懷疑這是一個E. cloacae泌尿道感染群突發，被汙染的輸尿管鏡可能是引起這次群突發的原因；在修改輸尿管鏡的消毒步驟後，成功的控制這次的群突發。

Ertapenem-resistant E. cloacae strains were isolated from the urine of 18 patients who underwent ureteroscopy in a regional hospital in southern Taiwan, from October to December 2010. We aimed at determining whether this was an outbreak of E. cloacae urinary tract infections (UTIs). Surveillance cultures were performed using the equipment and materials used for ureteroscopy, and 3 ertapenem-resistant E. cloacae strains were isolated. Hence, the disinfection protocols for ureteroscopy were revised, which included reinforcement cleaning, increase in the time of disinfection with 0.55% ortho-phthalaldehyde from 10 to 15 minutes, and ethylene oxide sterilization every week. A total of 21 ertapenem-resistant E. cloacae strains (18 from patients and 3 from ureteroscopy instruments) were isolated. All these strains had the same antibiotic susceptibility patterns; they were resistant to most antibiotics and sensitive to only amikacin, imipenem, and meropenem. After intervention using control practices, no E. cloacae strain was isolated from the ureteroscopy instruments, and none of the patients who underwent ureteroscopy had any ertapenem-resistant E. cloacae UTIs. Since the 21 E. cloacae strains isolated had same antibiotic susceptibility patterns and responded to similar management, we inferred that this episode was an outbreak of E. cloacae UTIs, and contaminated ureteroscopy instruments might be the cause of this outbreak, although lack of bacterial typing results confirmed. The outbreak was controlled after introduction of the revised disinfection protocols of ureteroscopy.